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Low energy electronic states and triplet pairing in layered cobaltates

G. Khaliullin·W. Koshibae·S. Maekawa
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Abstract

The structure of the low-energy electronic states in layered cobaltates is considered starting from the Mott insulating limit. We argue that the coherent part of the wave-functions and the Fermi-surface topology at low doping are strongly influenced by spin-orbit coupling of the correlated electrons on the $t_{2g}$ level. An effective t-J model based on mixed spin-orbital states is radically different from that for the cuprates, and supports unconventional, pseudospin-triplet pairing.

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G. Khaliullin, W. Koshibae, S. Maekawa. 2005-10-03. Low energy electronic states and triplet pairing in layered cobaltates. https://doi.org/10.1103/physrevlett.93.176401

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